A guide to your first grow room

So, you’re new to the world of indoor horticulture and you would like to set up a grow room and raise some plants at home. I won’t lie to you, this is a very difficult and daunting hobby to take up. But as with anything, mistakes will happen, it’s a learning curve and with experience follows knowledge. Don’t let this put you off starting up because there is plenty of enjoyment to get out of indoor horticulture and plenty of rewards to reap. Let’s go right to the start and help you to build a modest grow set up for a beginner with a low number of plants.

Firstly, you will need some space to set up your grow, wether this is a spare room, a loft/attic or even just some space in an already inhabited room, you will need a suitable space to grow.

Is it big enough?

Almost any space can be used for a grow room set up. You can convert an entire room into a grow space, use a cupboard or a wardrobe, or probably most popularly, a grow tent.

Have you got power?

For a small one or two light set up a normal dual wall socket will be fine. Make use of extension leads if you can’t plug equipment straight into the wall.

Is noise an issue?

Elements of your grow room can get quite noisy, especially with bigger grows. Determine wether nose in your chosen grow space will cause any issue for yourself, other members of the building, or neighbours.

What is the flooring like?

You shouldn’t grow straight onto a carpeted floor as they can hold moisture and harbour bugs and bacteria. You can put down reflective sheeting for a clean wipeable surface or a tray may be best.

Next, make sure you have a light tight environment if your plants have a specific light cycle. You can use blackout reflective sheeting to cover windows and light sources as it stops light escaping and keeps natural light out of your set up. Plants can get confused and stressed with inconsistent exposure of light. If your plant does not require a specific light cycle then you need not worry about this. Also if you have a grow tent, these are usually light tight enough to not have to worry about modifying the room which it is in, but of course refrain from using your house lights while your plant is growing.

Once you have your space, next you must configure your set up. There are three options here:

1: Convert an entire room into a grow room. This will entail covering the walls with reflective sheeting, like you would find inside of a grow tent. Also note that one light will not be enough and will cause your plants to under perform. You will need one grow light per every 1.2m x1.2m as a minimum. Filling the room with tents will make it a lot easier to control your environment.

2: Room within a room. The best way and usually cheapest way to create a grow room is to buy a grow tent. Advantages of this are, maintaining the optimum climate, preventing bug infestations and diseases, minimising light loss and protecting the rest of the room from the humidity and the heat in your tent. The tent you need depends on what you’re growing and which lights you will use. For tall plants and high intensity lighting you will need bigger and taller tents.

Option 3: Convert an enclosed room set up. This could be anything from an empty wardrobe to a cupboard, however you may encounter some heat problems. To prevent this choose a space with some height, 5 foot tall should be good but ideally you want more. Use nothing more powerful than a 250 – 315w light, and ensure there’s a constant flow of new air into your set up. In order to ensure you get a constant flow of cool air, use an extractor fan to get rid of hot air. Also make sure there are input holes in your grow room (you can make these yourself) to bring new air inside.

Now it’s time to decide what light is best for you. A typical grow light is made up of a ballast, lamp, and reflector. A main grow light is essential for any grow room but there are a few that you can choose from, such as:

Metal Halide: Great for vegetative growth

Sodium: Great for flowering

Dual Spectrum HPS: For veg and flowering

LED’s: For use throughout your grow

When choosing a grow light you really need to think about how much power the light uses, how much light it gives out, and how much space you have in your grow room and try to find the one  which fits best with you. Remember LED lights do not give off much heat so this may benefit an enclosed room set up. However for a larger grow room where heat is needed you may not want to choose an LED light, if you do, you may need a heater to keep the temperature right. You can always use LED light strips to supplement your existing lighting. In addition, with LED lighting still a relatively new technology when it comes to growing, and can be very pricey. We will cover the topic of LEDs very soon in another post!

You should seriously consider an air exchange system for your grow room. Plants are always consuming CO2 and releasing moisture, and your lights will produce heat. In order to replace the stale, CO2 depleted, hot, moist air to a fresh, CO2 rich air you will need some sort of exchange system in place. As a general rule the more lights you have the better your air exchange system needs to be.

Extractor fans draw air out of your grow room. A method we usually use to determine how many you need in your set up is firstly by multiplying your tents length, width and height, to determine how much space is covered by your grow lights. Then, multiply this by 60 and this should tell you how many metres cubed of air you need to extract every hour. To be on the safe side use a fan controller. This will speed up the fan or slow it down depending on how hot your grow room is. Please note that extractors on the bigger side tend to be noisier.

Remember, for all the air leaving your grow room, fresh air needs to enter! With a small grow room set up with only 1 light it will usually be okay to use a series of vents to bring air in, but in a larger set up you will need an intake fan. This intake fan should run at 15-20% less than your extraction fan. If you are using both an intake and an extractor then they should be positioned on opposite sides of your grow room.

Finally, now you have your first grow room set up, here are a few safety tips you should keep in mind!

  • Use cable ties when necessary to keep wiring neat and out of the way.
  • Ensure that ballast and other electrical devices don’t come into contact with water.
  • Every so often check all installations connections and wiring.
  • Make sure your grow room is off limits to children and animals.
  • Read all instructions and safety information on products to be sure.
  • Consider a grow room friendly fire extinguisher.
  • Always uncoil extensions and don’t coil up reflector cables, as they can get hot and burn.

Well done! You have successfully completed your first grow room! Now it’s time to get growing! Click here to find out how to gain the optimum environment in your grow room and how to get the best yield from your chosen plant!

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